The present invention relates to a prosthesis for hip joint replacement and includes a femoral component having a stem extending from a proximal end to a distal end intended for implantation in a prepared cavity of the femur, an integral neck extending from such proximal end and a ball or head adapted to be affixed to the neck. As is well known in the art of hip replacement, the ball is intended to be received in an acetabular cup member.
It is important to prevent movement between the ball or femoral head and the neck as any such movement can cause corrosion and wear on the surface of the neck and on the adjoining surface of the ball or head. Any such corrosion can lead to the formation of debris and premature wearing of the prosthesis. A study of such corrosion and wear was reported in an article entitled "Corrosion and Wear At the Modular Interface of Uncemented Femoral Stems" by Stephen D. Cook, Robert L. Barrack and Alistair J. T. Clemow appearing on pages 68-72 of the Journal of Bone and Joint Surgery, Vol. 76-B, 1994 No. One (January). Another study was reported in an article entitled "An Analysis of the Head-Neck Taper Interface in Retrieved Hip Prostheses", by Jay R. Lieberman, Clare M. Rimnac, Kevin L. Garvin, Robert W. Klein and Eduardo A. Salvath, appearing on pages 162-167 of Clinical Orthopaedics and Related Research, Number 300, March 1994.